The result of which would be 0.5^2.2 = 0.217637641. To correct a colour input, you would need a function like so. c is our colour input and f is the gamma value to use. The major difference here is the use of setcomp in order to operate on each colour channel individually.

Note that Renderman is smart enough to recognise that although we have two functions with the same name called “gammacorrect” – they are returning two different types of data – one being a floating point number the other being a colour. As long as the variable you are passing the data into – in this case “myColour” – is of the correct type, it’ll know what to do with it.